Ammonia excretion by zooplankton and its significance to primary productivity during summer

✍ Scribed by M. Jawed

• Book ID: 104751182
• Publisher: Springer-Verlag
• Year: 1973
• Tongue: English
• Weight: 596 KB
• Volume: 23
• Category: Article
• ISSN: 0025-3162
• DOI: 10.1007/bf00389168

✦ Synopsis

Excretion rates of ammonia have been determined for zooplankton off the coasts of Washington and Oregon (USA). Rates varied from 0A6 to 0.60 t~g-at Ntt+-N/mg dry weight/ day for most planktonic animals, and from 0.02 to 0.06 for jellyfishes. Ammonia concentration in seawater was low in offshore regions. Ammonia released by zooplankton was studied in relation to primary productivity during summer. It was found that, in the Columbia River plume offshore, excreted ammonia contributed about 90 % of the total nitrogen requirements of observed production rates. The ammonia-N contribution was 36 % in oceanic waters, and was relatively unimportant in the inshore region. The significance of eddy diffusivity in offshore waters and upwelling in inshore waters is also discussed.